JPS62195307A - Fungicide for agricultural and horticultural use - Google Patents

Abstract

PURPOSE:To provide an agricultural and horticultural fungicide containing 1-(substituted phenyl)-2,6-diphenyl-4(1H)-pyridinone as an active component and exhibiting excellent fungicidal effect against the pathogen of sheath blight of rice plant. CONSTITUTION:The objective agricultural and horticultural fungicide contains a 4(1H)-pyridinone derivative of formula I (X is halogen, alkoxy, hydroxy, nitro, phenyl or amid) [e.g. 1-(2-chlorophenyl)-2,6-diphenyl-4(1H)-pyridinone] as an active component. The compound of formula I can be produced e.g. by reacting 1,5-diphenylpentanetrione of formula II or its tautomer with an aniline derivative of formula III. The ratio of the active component in the fungicide is preferably 0.5-20wt% for powder or granule and 5-80wt% for emulsifiable concentrate or wettable powder.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel fungicide for agriculture and horticulture. More specifically, the present invention relates to an agricultural and horticultural fungicide that has excellent fungicidal activity against rice sheath blight fungi.

Among conventional agricultural and horticultural fungicides, rice sheath blight control agents are particularly important for rice cultivation. Conventionally, organic arsenic agents have been used to control this rice sheath blight disease, but due to environmental pollution, residual toxicity, and other reasons, there has been a demand for alternative agents, and as a result, antibiotics such as polyoxin and validamycin have been used. It has been developed. However, these antibiotics have drawbacks such as being expensive, insufficiently effective, and unstable, and there is a desire for the development of a new drug for controlling rice sheath blight.

By the way, in recent years, the physiological activity of 4(IH)-viridinone derivatives has attracted attention, and research on their use as agricultural and horticultural agents has been conducted. -Viridinone derivatives have been discovered (JP-A-55-102504, JP-A-56-
65871).

However, this product has the disadvantage that it cannot effectively control rice sheath blight.

Problems to be Solved by the Invention The object of the present invention is to find a 4(IH)-viridinone derivative that has particularly excellent bactericidal activity against rice sheath blight fungi, and to create a product containing this 4(IH)-viridinone derivative as an active ingredient. The purpose of the present invention is to provide a novel agricultural and horticultural fungicide.

Means for Solving the Problems In order to achieve the above object, the present inventors have developed various 4 (
As a result of producing IH)-viridinone derivatives and examining their bactericidal activity, we found that they are expressed by the general formula (wherein X is a rogen atom, an alkoxy group, a hydroxy group, a nitro group, a phenyl group, or an amine group). The present inventors have discovered that 4 (I Ij)-viridinone derivatives are excellent as agricultural and horticultural fungicides, particularly as agents for controlling rice sheath blight, and have completed the present invention based on this knowledge.

That is, the present invention provides 4 represented by the general formula (1) above.
The present invention provides an agricultural and horticultural fungicide characterized by containing a (1H)-viridinone derivative as an active ingredient.

The 4(IH)-pyridinone derivative represented by the general formula (I) is a known compound, and 1,5-diphenyl-L
Reaction of 4-pentadiin-3-one with various anilines (
It can be produced from two [[Kombuchi Rendo (
Comptes rendus) J Vol. 224, pp. 476-478 (1947), "Anale.

Annales de chimie
) J Vol. 12, No. 3, pp. 393-444 (1
948), “Fretan° Société° Simy° France (Bu/11).

S□c,C! him, France) J No. 734~
739 pages (1954)]. However, the physiological activity of this compound is completely unknown so far.

Specific examples of the 4(IH)-viridinone derivatives represented by the general formula (1) used in the present invention (:) are shown in Table 1. The compound numbers in the table will be followed in the following description. Ru.

Table 1? D4 (I H)-viridinone derivatives are available from the aforementioned 1 Pretans Société Chimy France (Bull
.

Boa, Chin, France) J No. 734~
It can be produced according to the known method described on page 739 (1954) or according to the method shown below.

That is, 1,5-diphenylpentantrione (If) or its tautomer (...a), (I
Aniline derivatives represented by [t)), ([0), (■d) and (II) (■a) JT (■b) (lid) (no) (having the same meaning as in the formula or above) A 4(1H)-pyridinone derivative represented by the general formula (I) can be obtained by reacting the above.

This reaction is carried out in general (=, pentantrione represented by formula (I[) or formula (Il&), (Ul)), (I[C)
The tautomer represented by
Halogenated hydrocarbons such as chlorobenzene, methylene chloride, and chloroformnat; ethers such as diisopropyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; esters such as ethyl acetate; nitrites such as acetonitrile; .

It may be carried out by dissolving or suspending it in amides such as N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, acetic acid, etc., or it may be carried out without using a solvent. , xylene or chlorobenzene. In this case, the reaction may be carried out by adding a suitable reaction aid if desired.

As the reaction aid, suitable acids such as mineral acids such as sulfuric acid and hydrochloric acid, organic acids such as p-toluenesulfonic acid and trifluoromethanesulfonic acid, Lewis acid such as boron trifluoride, aluminum chloride, and titanium tetrachloride are used. Examples include acids. Furthermore, the reaction can be allowed to proceed while the water produced by the reaction is collected using a Dean-Stark trap or the like.

Furthermore, depending on the reaction aid and solvent used, the reaction can be carried out in the presence of a dehydrating agent such as molecular sieves. For example, when using p-)luenesulfonic acid in dimethylsulfoxide, it is preferable to use molecular sieves 5A. The amount of molecular sieves used is usually 2 to 200 g, preferably 50 g, per 0.1 mole of 1,5-diphenylpentantrione.
~200g.

Regarding the reaction temperature, the reaction can be carried out at any temperature from the freezing point to the boiling point of the solvent, preferably from 10°C to the boiling point of the solvent. The desired compound can be obtained by washing with water or removing it by means such as filtration, then extracting the reaction product with chloroform or the like, and then removing the solvent. This product can be purified by recrystallization from acetone, methanol, ethanol, benzene, toluene, diisopropyl ether, ethyl acetate, chloroform, hexane, etc. (by dilution, or by silica gel column chromatography, if necessary).

In addition, 4 (1)1)- represented by the general formula (1) above
As another method for producing viridinone derivatives, the following general formula (N)
5-anilino-1,5-diphenyl-4- represented by
Pentene-1,3-dione derivative or general formula (lV&)
, (IVt)), (IVC), (IVd), (■e) There is a method of ring-closing the tautomers thereof in the presence of an acid catalyst.

(■) (■a) (■b) Ji (X in the formula has the same meaning as above) In this method, 5-anily/-1,5-diphenyl-4-pentene- 1,3-dione derivative or its tautomer (lVa), (IVb),
(IVC), (■d), and (IVe) are combined with a suitable solvent, such as hydrocarbons such as evabenzene, toluene, and xylene, halogenated hydrocarbons such as chlorobenzene, methylene chloride, and chloroform, diisopropyl ether, tetrahydrofuran, and dioxanate. ethers, acetone,
Ketones such as methyl ethyl ketone, nitriles such as acetonitrile, N,N-dimethylformamide, N
, amides such as N-dimethylacetamide, and further (;
may be dissolved or suspended in dimethyl sulfoxide, acetic acid, etc. for ring closure, or may be ring closed without using a solvent.

Examples of the acid catalyst include polyphosphoric acid, sulfuric acid, p-toluenesulfonic acid, and aluminum chloride. Regarding the reaction temperature, the reaction can be carried out at any temperature from the freezing point to the boiling point of the solvent, preferably at a temperature in the range from 10°C to the boiling point of the solvent.

After the reaction is completed, ice water is added to the reaction solution, extracted with chloroform, etc., washed with water, dried, and the solvent is distilled off to obtain the desired compound. This product can be purified, if necessary, by recrystallization from benzene, toluene, methanol, chloroform, ethyl acetate, acetone, hexane, etc., or by silica gel column chromatography.

The 4(IH)-viridinone derivative represented by the general formula (1) thus obtained has a bactericidal activity, particularly an excellent bactericidal activity against the rice sheath blight fungus.

Although the agricultural and horticultural fungicide of the present invention may be used as the compound itself, it is usually mixed with a carrier, a surfactant, a dispersant, or an auxiliary agent and prepared in a conventional manner, for example, as a powder, wettable powder, or emulsion. ,
It is used after being formulated into fine granules or granules.

Suitable carriers include, for example, solid carriers such as talc, bentonite, clay, kaolin, diatomaceous earth, white carbon, vermiculite, slaked lime, silica sand, ammonium sulfate, and urea, and liquid carriers such as isopropyl alcohol, xylene, and cyclohexanone. It will be done. Examples of surfactants and dispersants include alcohol sulfate salts, alkyl sulfonate salts, lignin sulfonate salts, polyoxyethylene glycol ethers, polyoxyethylene alkylaryl ethers, and polyoxyethylene sorbitan monoalkylates. Examples of the adjuvant include carboxymethyl cellulose, polyethylene glycol, and gum arabic. These preparations can be diluted to an appropriate concentration and sprayed, or applied directly.

The blending ratio of the active ingredient is selected as appropriate depending on the need, but in the case of powder or granules, it is 0.5 to 20% by weight;
When used as an emulsion or a wettable powder, a range of 5 to 80% by weight is appropriate.

The application amount of the agricultural and horticultural fungicide of the present invention depends on the type of compound used, target disease, occurrence tendency, degree of damage, environmental conditions,
The dosage form used, etc. (= This varies depending on the formulation, but when used as is, such as powders or granules, the active ingredient should be selected appropriately from the range of 10 to 500 I per 10 ares. If it is to be used in liquid form, it should be added as appropriate from the range of 10 to 1000 ppm (=
It's good to choose.

Effects of the Invention The agricultural and horticultural fungicide of the present invention has a wide antibacterial spectrum against paddy rice and horticultural diseases such as rice sheath blight, rice blast, cucumber downy mildew, cucumber powdery mildew, and Japanese mustard rot. However, it is particularly effective as a control agent for rice sheath blight. This activity is expressed both prophylactically and therapeutically, and is persistent.

Furthermore, it has excellent characteristics such as being highly safe for crops, mixed-breed animals, and fish and shellfish.

Example Next, the present invention will be further explained with reference to Examples.

In addition, the term ``in Examples'' means weight.

L5-diphenyl-1; 3,5-pentantrione 11
．． 211 (0,042 mol), 2-chloroaniline 4
2.6 // (0,,53 mol), p-)luenesulfonic acid 6, Ofi (0,032 mol) and Molecular Sheeps 5 A 45,077 in 300 ml of xylene
and refluxed for 3 hours. After cooling, solid matter was removed, and the organic layer was washed with 100 m/1 of 10% hydrochloric acid, followed by 100 g/1 of a 10% aqueous sodium hydroxide solution, further washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off.

Next, the resulting residue was crystallized from a mixed solvent of acetone/hexane (1/1), and 1-
(2-chlorophenyl)-2,6-diphenyl-4(I
4.5 g of H)-viridinone were obtained.

Example 1 (Powder) A compound (2% of solubility, ±5% of silicon ring and 93 pieces of clay) was uniformly mixed and pulverized to obtain a powder.

Example 2 (Wettable powder) A wettable powder was prepared by uniformly mixing and pulverizing 50 units of compound (2), ±45 units of diatoms, 2% of sodium naphthylmethane disulfonate, and 3 units of sodium ligninsulfonate.

Example 3 (Emulsion) An emulsion was prepared by uniformly dissolving 50% of compound (3), 20% of cyclohexanone, 11% of polyoxyethylene alkylaryl ether, 4% of calcium alkylbenzenesulfonate, and 35% of methylnaphthalene.

Example 4 (granules) Compound (4) 5%, sodium salt of lauryl alcohol sulfate 2%, sodium lignin sulfonate 5Ss carboxymethyl cellulose 2%, and clay 8
Mix and grind 6 pieces uniformly. This mixture was kneaded with 20 g of water, processed into granules of 14 to 32 mesh using an extrusion type granulator, and then dried to form granules.

Fifteen rice seeds (variety: Zennanfu) were sown in each clay body with a diameter of 73 mm, and grown in a greenhouse for 4 to 5 weeks. A hydrating powder prepared according to Example 2 was diluted with water to a predetermined concentration and sprayed at 10 g per pot to rice seedlings in which the fifth leaf had developed.

After air-drying, the sheath blight fungus (
Rh1Z□ctoniaeolani) was inoculated at the base of the plant, placed in a greenhouse (28°C), and 5 days later, the length of the lesion formed on the rice leaf sheath was measured, and the control value was calculated according to the following criteria.

The results are shown in Table 2.

Table 2 Patent applicant: Kumiai Chemical Industry Co., Ltd. and 1 other person

Claims (1)

[Claims] 1 General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (X in the formula is a halogen atom, an alkoxy group, a hydroxy group, a nitro group, a phenyl group, or an amino group) 4 ( An agricultural and horticultural fungicide characterized by containing a 1H)-pyridinone derivative as an active ingredient.